If your ship needs buffing out, I'd do that first. That way you won't hurt the tape, because your going to replace it later, anyway. Next, I would not worry about the internal seals (I have proven to myself that properly applied Mylar seals is all that is needed). Lastly, I remove the grease and goo with Acetone, having used it for 40 years with no adverse effects to gelcoat or urethane....................flame suit on!
Have fun,
JJ